title: Primary structure of avian hepatic rhodanese.
abstract: Rhodanese (thiosulfate: cyanide sulfurtransferase, EC 2.8.1.1.) was purified from chicken livers and its amino acid sequence was determined. The enzyme has a specific activity of 676 IU and a molecular weight of 32,255. The primary structure of 289 amino acids was solved by sequential Edman degradation of overlapping peptides obtained by selected enzymatic and chemical cleavages. The amino terminus was blocked, and the carboxy-terminus was heterogeneous. Comparison of the primary structure with bovine liver rhodanese showed 212 identically matched amino acids, and the majority of amino acid differences were conservative substitutions. Reaction of the enzyme with a 1.4-fold molar excess of [2-14C]iodoacetate led to inactivation of the enzyme and carboxymethylation of Cys-244; this modification was blocked by the substrate thiosulfate.
authors.affiliation: Department of Biochemistry, Mount Sinai School of Medicine, New York, New York 10029.
authors.forename: R A
authors.initials: RA
authors.lastname: Kohanski
authors.forename: R L
authors.initials: RL
authors.lastname: Heinrikson
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D002645:Chickens / Q000378:metabolism*; D003488:Cyanogen Bromide; D003545:Cysteine / Q000032:analysis; D007461:Iodoacetates / Q000494:pharmacology; D019807:Iodoacetic Acid; D008099:Liver / Q000201:enzymology*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D012689:Sequence Homology, Nucleic Acid; D013884:Thiosulfate Sulfurtransferase / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D014357:Trypsin
chemical_list: D000596:Amino Acids; D007461:Iodoacetates; D010446:Peptide Fragments; D013884:Thiosulfate Sulfurtransferase; D014357:Trypsin; D003545:Cysteine; D003488:Cyanogen Bromide; D019807:Iodoacetic Acid